JP7386835B2 - lighting equipment - Google Patents

Description

The present disclosure relates to a lighting device, and particularly to a lighting device that simulates natural scenery such as the sky seen through a window.

There are lighting devices that simulate natural scenery such as the sky seen through a window (see, for example, Patent Documents 1 and 2). The illumination system described in US Pat. No. 5,001,302 includes one or more sidewalls defining a recess and a light-transmitting or light-generating region located at the bottom of the recess. Further, in the lighting system, at least one of the side walls has a rectangular light emitting area formed from independently controllable triangular light emitting areas, and controlling the shape, contrast, intensity or color of the light provided at the side wall. Equipped with lighting equipment for With this configuration, if the light transmitting or light generating area located at the bottom of the recess on the side wall were an actual window, it would be possible to reduce the amount of sunlight that would be formed by sunlight that would come in through the window (hereinafter also referred to as incoming light). The shadow area and the shadow area are simulated.

Further, the lighting system described in Patent Document 2 includes a light source and a lamp umbrella-like structure. The lamp umbrella structure includes a screen structure and a bottom body, the bottom body having a diffused light generator that acts as a Rayleigh diffuser. In the illumination system, the light source is arranged to illuminate the entire upper surface of the diffuse light generator at a principal ray angle of about 60 degrees. By arranging the light sources in this way, the user can recognize the diffused light emitted from the diffused light generator as light that simulates a blue sky, and the chief ray that passes through the diffused light generator can be recognized as direct light from the sun. It can be recognized as In this configuration, when the user views the diffused light generator, it appears that the sun is located on the other side of the diffused light generator that simulates a window.

International Publication No. 2015/055430 Japanese Patent Application Publication No. 2015-207554

However, the configuration shown in Patent Document 1 includes a light-emitting panel portion that simulates the sky seen through the window (corresponding to the light-transmitting or light-generating region located at the bottom of the recess), and a light-emitting panel portion that simulates the sky seen through the window (corresponding to the light-transmitting or light-generating region located at the bottom of the recess), and a light-emitting panel portion that simulates the sunlight that illuminates the window frame. It is necessary to arrange light sources for different purposes on the side wall portions forming the shaded area and the shadow area. Specifically, it is necessary to arrange a light source for simulating a blue sky on the light emitting panel portion, and a light source for simulating inserted light on the side wall portion. The color, intensity, and distribution of light that the user wants to see differs between the light-emitting panel that simulates the sky through the window and the side wall that simulates the incoming light that illuminates the window frame, so it is necessary to place the appropriate light source for each. . As described above, when it is necessary to arrange different light sources at a plurality of locations in a lighting device, there are problems such as an increase in the size of the device and a complicated configuration due to a mechanism for dissipating heat emitted from the light source, wiring, and the like. Furthermore, as the number of light sources increases, the amount of energy consumed also increases, which is not desirable from the viewpoint of energy saving.

In addition, in the configuration shown in Patent Document 2, the emission surface of the light emitting panel not only emits scattered light that simulates the sky, but also emits transmitted light that simulates direct sunlight, so that the viewer can see the sky. The structure makes it appear as if you are looking into the sun through a light-emitting panel that simulates the sun. Therefore, from the observer's perspective, the sun will always be located within a light-emitting panel that simulates a single window (equivalent to a diffused light generator that works as a Rayleigh diffuser). When considering arranging a plurality of lighting devices to simulate windows, there is a problem in that a natural landscape cannot be reproduced. In other words, the configuration shown in Patent Document 2 makes it appear as if the viewer is looking into the sun through a light-emitting panel that simulates the sky, so there are restrictions on where and how many panels can be placed. There are problems like this.

In view of the above-mentioned points, the present disclosure realizes smaller size and simpler structure by using a common light source for simulating the sky seen through the window and a light source for simulating the incoming light illuminating the window frame. It is an object of the present invention to provide a lighting device capable of reproducing a natural landscape without placing any restrictions on the placement location or the number of placements.

The lighting device according to the present disclosure includes:
a light source and
a first light exit surface that has a scattering structure that scatters the incident light, and that emits at least one light entrance surface and a first exit light that includes the scattered light generated by the scattering structure; a second light emitting surface that emits a second emitted light different from the emitted light, and receives light from the light source to generate the first emitted light and the second emitted light; body and
a sunshade forming part that is provided at at least one position around the diffuser, has a light-transmissive member, and forms a sunshade using the second emitted light ;
a folding section that guides the second emitted light toward the sunlight forming section;
a light shielding part provided at at least one position between the first light emitting surface and the sun forming part and blocking the first emitted light from entering the sun forming part; It is characterized by being prepared.

According to the present invention, in a lighting device that reproduces the sky seen through a window, it is possible to realize a smaller size and a simpler structure, and to reproduce a natural landscape without placing restrictions on the location or number of devices. can.

1 is a cross-sectional view showing a configuration example of a lighting device 200 according to Embodiment 1. FIG. It is an explanatory view showing an example of the optical path of light in a diffuser. It is an explanatory view showing the optical path of the 2nd emitted light to the sunshine formation part. 3 is a configuration diagram showing another example of the lighting device 200. FIG. It is a block diagram which shows another example of a folding part. It is a block diagram which shows another example of a folding part. It is a block diagram which shows another example of a sun formation part. 2 is a front view showing an example of a lighting device 200. FIG. 2 is a perspective view of an example of a lighting device 200. FIG. 3 is a cross-sectional view showing another example of the lighting device 200. FIG. 2 is a cross-sectional view showing an example of a lighting device 200. FIG. 2 is a perspective view of an example of a lighting device 200. FIG.

Embodiments of the present disclosure will be described below with reference to the drawings. The following embodiments are merely examples, and it is possible to combine the embodiments as appropriate and to make various changes within the scope of the technical matters indicated in the present disclosure. Further, in the drawings below, dimensions may be shown on different scales depending on the component. Furthermore, in each of the following embodiments, coordinate axes of an XYZ orthogonal coordinate system may be shown in each figure for ease of explanation. In this case, the normal direction of the main light emitting surface of the diffuser is defined as the -Y axis direction. Note that the normal direction of the main light emitting surface of the diffuser is also referred to as the main emission direction of the diffuser and the illumination direction of a lighting device including the diffuser. Further, among the directions perpendicular to the main emission direction, a direction close to the traveling direction of the light incident on the diffuser is defined as the +Z-axis direction.

Here, the main light emitting surface of the diffuser refers to a particularly determined surface among the light exit surfaces provided in the diffuser. More specifically, the main light emitting surface is the light emitting surface from which the diffuser emits light, and is the surface that the user wants to see as a window to look into the sky, or more technically, as a light emitting surface that simulates the sky. That's fine.

For example, in the case of a plate-shaped diffuser in which two surfaces are connected by side surfaces, the main light emitting surface is at least one of the two surfaces connected by side surfaces. Note that there may be two or more main light emitting surfaces. For example, if the main light emitting surface is a plate-shaped diffuser in which the two surfaces are connected by the side surfaces, the main light emitting surface may be two surfaces connected by the side surfaces. Hereinafter, when the diffuser is plate-shaped, two surfaces connected by a plate-shaped side surface will be referred to as the main surface, and a surface connected to the end of the main surface and forming the plate-shaped side surface will be referred to as an end surface. Sometimes called a side.

Further, for example, if the main light emitting surface is a rod-shaped diffuser in the shape of a column in which two bottom surfaces are connected by a side surface, the main light emitting surface may be at least one or a part of the side surface of the column. . Hereinafter, when the diffuser is rod-shaped, the side surface connected to the rod-shaped bottom (or the outer surface of the side surface if hollow) is referred to as the main surface. The surface that forms this is sometimes called an end surface or a side surface.

For example, the main light emitting surface of a diffuser may be a surface of the main surface whose normal direction faces indoors when a lighting device including the diffuser is installed in place of a window, or a part thereof. good.

Note that the main light emitting surface is not limited to a flat surface, and may include, for example, a curved surface or an inclined surface. The main light emitting surface may be curved or inclined, for example, or may be a combination of such flat surfaces, curved surfaces, or inclined surfaces. When the main light emitting surface is other than a flat surface, the normal direction of the main light emitting surface may be the normal direction of the center or the normal direction of the tangential plane. Note that in cases where all the side surfaces of the cylinder are used as the main light emitting surface, or when the main light emitting surface forms all the outer edges in the YZ cross section, the normal direction of the main light emitting surface may be radial.

Embodiment 1.
Hereinafter, a lighting device according to Embodiment 1 of the present disclosure will be described with reference to the drawings.

<Configuration of lighting device 200>
FIG. 1 is a cross-sectional view showing a configuration example of a lighting device 200 according to the first embodiment. For example, when the lighting device 200 shown in FIG. 1 is attached to a ceiling surface indoors, the +Y-axis direction is the ceiling side, and the -Y-axis direction is the indoor side. Further, the ZX plane in this case may be a plane parallel to the ceiling surface. Further, for example, when the lighting device 200 shown in FIG. 1 is attached to an indoor wall, the +Y-axis direction is the wall side, and the -Y-axis direction is the indoor side. Further, the ZX plane in this case may be a plane parallel to the wall surface.

The illumination device 200 according to the first embodiment includes a light source 1 , a diffuser 100 , a folded portion 2 , and a sunlight forming portion 3 . Further, the lighting device 200 may further include a back plate 4 and a light shielding section 5. Furthermore, the lighting device 200 further includes a holding section 6 that holds each member.

<Diffuser 100>
Diffuser 100 has a light entrance surface 101a and a light exit surface 101b. In the example shown in FIG. 1, the main light emitting surface is the light emitting surface 101b. Note that the main light emitting surface may be a part of the surface 101b.

Hereinafter, the light incident on the diffuser 100 may be referred to as light Li. Further, the scattered light generated within the diffuser 100 may be referred to as light Ls. Furthermore, hereinafter, the light guided within the diffuser 100 may be referred to as light Lt or propagation light Lt. Here, "light guiding" refers to propagating light that has entered a certain medium along a predetermined optical path within the medium. Further, in the following, the light Ls emitted from the main light emitting surface (in the example of FIG. 1, the light emitting surface 101b, also referred to as the first light emitting surface) of the diffuser 100 will be referred to as the first emitted light or the light L1. call. Furthermore, as will be described later, the light emitted from the second light emitting surface (the light emitting surface 101c in the example of FIG. 1) located on the opposite side of the light incident surface of the diffuser 100 is converted into the second emitting light. Alternatively, it is called light L2.

FIG. 2 is an explanatory diagram showing an example of the optical path of light within the diffuser 100. As shown in FIG. 2, the diffuser 100 receives the light Li emitted from the light source 1 from the light entrance surface 101a, which is one of the end faces, and scatters a part of the light while guiding it inside as light Lt. Then, it is emitted from the light emitting surface 101b as the first emitted light (L1).

In the example shown in FIG. 2, the light Li is transmitted along the +Z axis from the end side of the light exit surface 101b, which is the main light emitting surface of the diffuser 100 (specifically, from the light entrance surface 101a, which corresponds to the end surface of the diffuser 100). direction. The light Ls is generated by the scattering effect of the diffuser 100 on the light Li. By emitting such light Ls from the light emitting surface 101b, the diffuser 100 is visualized as a light emitter that emits light similar to the natural sky. Hereinafter, the diffuser 100 as a light emitter that emits the desired light L1 may be referred to as a light emitter 100 or a light emitting panel 100. Further, hereinafter, the surface on which the main light emitting surface is formed may be referred to as the front surface, and the surface on the opposite side may be referred to as the rear surface.

Light emitted from the light source 1 enters the diffuser 100 from the light incidence surface 101a of the diffuser 100, and is guided inside the diffuser 100. Furthermore, at least a portion of the light guided through the diffuser 100 is scattered and then emitted from the diffuser 100 . More specifically, the light guided within the diffuser 100 becomes scattered light by being scattered within the diffuser 100, and at least a part of it is transmitted from the light exit surface 101b as the first emitted light (light L1). It is emitted. Here, the light emitting surface 101b emits at least a portion of the light Ls scattered by the scattering structure of the diffuser 100.

Furthermore, among the light incident on the diffuser 100, the light guided within the diffuser 100, and the light scattered within the diffuser 100, at least a portion of the light excluding the light emitted from the light exit surface 101b is , is emitted as second emitted light from the light emitting surface 101c. More specifically, among the light incident on the diffuser 100, the light guided in the diffuser 100, and the light scattered within the diffuser 100, the light output is arranged at a position facing the light incidence surface 101a. At least a portion of the light that has reached the surface 101c is emitted from the light emitting surface 101c.

For example, light Li entering from the light incidence surface 101a of the diffuser 100 is reflected and guided as light Lt by the surface 101b (front surface) and the surface 101d (back surface). The light Lt is guided by, for example, total internal reflection. A part of the light Lt guided through the diffuser 100 is scattered by the scattering structure included in the diffuser 100, and exits from the light exit surface 101b as light L1. Viewed locally, part of the light Lt guided within the diffuser 100 that is not scattered, or a portion of the scattered light that is not emitted from the light exit surface 101b, further travels within the diffuser 100. Transmits and guides light. The light is scattered by, for example, another scattering structure included in the diffuser 100 and exits from the light output surface 101b as light L1. In this way, the light incident on the diffuser 100 is multiple scattered by the scattering structure. On the other hand, at least a portion of the light that is not emitted from the light exit surface 101b of the diffuser 100 reaches the end surface facing the light entrance surface 101a.

In this example, a light exit surface 101c is provided on the end surface facing the light entrance surface 101a for outputting to the outside the light that is not emitted from the light exit surface 101b among the light that has entered the diffuser 100. In this example, the light exit surface 101b is the first light exit surface, and the light exit surface 101c is the second light exit surface. The light emitted from the light emitting surface 101c is deflected by the folding section 2, which will be described later, and is emitted from the sunlight forming section 3 as light simulating the inserted light.

In the diffuser 100, the first light emitting surface (light emitting surface 101b) is a surface that emits first emitted light that simulates the sky. Further, the second light output surface (light output surface 101c) is a surface that outputs second output light that simulates inserted light.

In this way, the illumination device 200 is configured to input light from the end face of the diffuser 100 and emit the first output light simulating the sky from the main surface of the diffuser 100, so that the illumination device 200 It can be made thinner than a configuration in which light enters from the back side. Furthermore, the lighting device 200 has a configuration in which the sunlight forming part 3 expresses the incoming light of sunlight, unlike a configuration in which light simulating direct sunlight is emitted along with scattered light simulating the sky from the main surface. By adopting this technology, a natural landscape can be reproduced without the need for the viewer to look into the simulated sun through a light-emitting panel. Therefore, a natural landscape can be reproduced without any restrictions on the location or number of locations.

An example of the diffuser 100 is a light guide panel that is a light-transmitting member that transmits, reflects, and guides light while diffusing (scattering) a portion of the light. More specific examples include those having a base material such as a transparent resin and a scattering structure for scattering light. Examples of scattering structures include particles with a different refractive index than the substrate, crystals, compositions such as sol-gel cured oxides, voids, uneven structures, and the like. Note that the specific configuration of the diffuser 100 is not limited as long as it is a structure having scattering ability.

The interior of the diffuser 100 may be filled with a refractive material and a scattering structure, for example. Examples of refractive materials include transparent resin, glass, or silicone materials. The material of the diffuser may be any material as long as it has light transmittance. From the viewpoint of light utilization efficiency, it is desirable that the light transmittance of the material of the diffuser be as high as possible. Further, since the diffuser 100 is disposed near the light source, the material of the diffuser is preferably a material with excellent heat resistance.

Diffuser 100 can include multiple types of scattering structures. In that case, the diffuser 100 may have the average size of the plurality of types of scattering structures in the size order shown below, or may have the size of any one type of the plurality of types of scattering structures in the size order shown below. good. Note that even in the former case, it is preferable that at least one of the plurality of types of scattering structures has the size order shown below.

Diffuser 100 includes, for example, a base material 110 and particles 111. Particles 111 are, for example, nanoparticles. A "nanoparticle" is a particle having a size on the order of nanometers (nm). Nanoparticles generally refer to particles with a size of 1 nm to several hundred nm. The particles 111 are, for example, particles whose particle size is on the nano-order. Further, the particles 111 may be, for example, microparticles. "Microparticles" are particles having a size on the order of micrometers (μm). Microparticles generally have a size of 1 μm to several thousand μm (eg, 5 mm or less). However, if the size of the particles is too large, the presence of the particles within the diffuser 100 will become noticeable, resulting in poor visibility such as a rough feeling. Therefore, the size of the particles 111 is preferably 3000 nm or less.

Particles 111 may be spherical or another shape.

Particles 111 are, for example, inorganic oxides. Examples of the inorganic oxide include ZnO, TiO ₂ , ZrO ₂ , SiO ₂ , Al ₂ O ₃ and the like.

The particles 111 scatter the light Li that has entered the diffuser 100 and convert it into light Ls. Further, the particles 111 scatter the light Lt propagated within the diffuser 100 to turn it into light Ls.

Base material 110 includes particles 111. Particles 111 may be added to base material 110. The particles 111 are, for example, dispersed in the base material 110.

The base material 110 is, for example, a transparent material, although it is not particularly limited. The base material 110 does not necessarily need to be transparent at all wavelengths of the light Li. As an example, the base material 110 may absorb a specific wavelength among the wavelengths of the light Li.

The transmittance (straight transmittance) of the base material 110 at a light guiding distance of 5 mm is preferably 90% or more at the design wavelength, more preferably 95% or more, and even more preferably 98% or more. Here, the design wavelength may be any predetermined wavelength among the wavelengths of incident light. The design wavelength is not limited to one wavelength, and may be a wavelength (wavelength band) having multiple wavelengths or widths. For example, when the incident light is white light, the design wavelength may be one or more wavelengths of 450 nm, 550 nm, and 650 nm. Note that the design wavelength may be three wavelengths: 450 nm, 550 nm, and 650 nm.

The base material 110 is, for example, solid. The base material 110 may be, for example, a resin plate using a thermoplastic polymer, a thermosetting resin, a photopolymerizable resin, or the like. Further, as the resin plate, an acrylic polymer, an olefin polymer, a vinyl polymer, a cellulose polymer, an amide polymer, a fluorine polymer, a urethane polymer, a silicone polymer, an imide polymer, or the like can be used. The diffuser 100 may be formed, for example, by performing a curing treatment on a material in which particles 111 are dispersed in the material of the base material 110 before curing. Note that the base material 110 is not limited to a solid material, and may be a liquid, liquid crystal, or gel-like substance.

Further, the diffuser 100 may be formed of, for example, a porous material made by a sol-gel method, an organic molecule-dispersed material, an organic-inorganic hybrid material (also referred to as an organic-inorganic composite material), or a metal particle-dispersed material. As an example, the diffuser 100 may be an organic/inorganic hybrid resin, for example, a hybrid resin of a resin and an inorganic oxide. In this case, the diffuser 100 has, as a substance equivalent to the particles 111, an inorganic oxide produced by sol-gel curing based on the base material 110 containing an inorganic oxide material and an organic compound. Note that fine pores and the like generated through such a manufacturing process may also be regarded as scattering structures.

Further, the diffuser 100 may be, for example, a base material 110 with fine irregularities formed on the surface thereof.

Further, the diffuser 100 may be provided with a light-transmitting functional coating such as an antireflection coating, an antifouling coating, a heat shielding coating, or a water repellent coating on at least one surface. Further, in consideration of functionality as a window (impact resistance, water resistance, heat resistance, etc.), the diffuser 100 may be sandwiched between two transparent substrates (for example, glass plates). You can. In this case, the diffuser 100 may be an interlayer film of laminated glass.

<Example of scattering phenomenon>
Hereinafter, as an example, a scattering phenomenon will be described when the diffuser 100 has a structure in which scattering particles are dispersed inside a transparent resin. The light Li that has entered the diffuser 100 from the light incidence surface 101a is guided within the diffuser 100 as light Lt. At least a portion of the light Lt guided through the diffuser 100 is scattered by the scattering particles. The light is then scattered with a dependence on the angle and the wavelength of the light. For example, if the size of the scattering particles is sufficiently small with respect to the wavelength of the colliding light (light Lt here), the scattered light Ls is isotropic and has a small dependence on the scattering angle, and is relatively small in wavelength. The scattering intensity of short wavelength light becomes higher than the scattering intensity of light with long wavelength.

On the other hand, when the size of the scattering particles is close to the wavelength of the colliding light, the degree of forward scattering of the scattered light Ls is relatively large compared to the backward scattering, and the scattering intensity is relatively large as described above. Generally speaking, light with shorter wavelengths has higher energy than light with longer wavelengths. Note that as the size of the scattering particles increases with respect to the wavelength of light, the degree of forward scattering increases and the wavelength dependence of the scattering intensity decreases.

Relatively, the scattering intensity by the scattering particles when the wavelength of the light Li is larger than the size of the scattering particles is lower than the scattering intensity by the scattering particles when the wavelength of the light Li is smaller than the size of the scattering particles. . Therefore, for example, when light Lt including a wide wavelength spectrum is incident on the light entrance surface 101a, the short wavelength light Lt is scattered more preferentially than the long wavelength light Lt. In this case, the correlated color temperature of the light (first emitted light) emitted from the light exit surface 101b of the diffuser 100 is higher than the correlated color temperature of the light Li incident on the diffuser 100. Such a color temperature relationship is effective for allowing the viewer to view the main light emitting surface of the diffuser 100 from which the first emitted light is emitted as a window into the natural sky. On the other hand, the light emitted from the light emitting surface 101c of the diffuser 100 (second emitted light) is the light scattered within the diffuser 100, excluding the first emitted light, among the light incident on the diffuser 100. (for example, forward scattered light) and unscattered light (light guide light), the color temperature of the light Li is lower than that of the first emitted light and is incident on the diffuser 100. Higher than correlated color temperature. Such a color temperature relationship (particularly a color temperature relationship between the first emitted light and the second emitted light) is such that the viewer can see the sunlight forming part from which the second emitted light is emitted. This is effective for making 3 visible as a window frame illuminated by sunlight.

Furthermore, according to the configuration of this embodiment, a more natural sky can be reproduced due to the angular dependence of the intensity of the first emitted light. For example, consider a case where the lighting device 200 of this embodiment is attached to an indoor ceiling. Assume that the light source 1 is fixed near the light entrance surface 101a, and an observer observes the first light exit surface (light exit surface 101b) from below. When an observer observes the first light emitting surface, the first emitted light (light L1) allows the observer to visually recognize the first light emitting surface as blue sky. Compared to when observed from directly below, which is the normal direction of the first light exit surface, it is higher when observed from an oblique direction approaching the traveling direction of the light Li (+Z-axis direction) from the normal direction (-Y-axis direction). Brightness is observed. This change in brightness is a phenomenon that occurs even in the natural sky, and when observing the natural sky, the brightness of the blue sky changes depending on the altitude and positional relationship with the sun. Therefore, according to the relationship between the light entrance surface 101a and the light exit surface 101b of the diffuser 100 described above, a more natural sky can be reproduced while being thin.

Note that the above example can be expressed as follows using the angular dependence of the intensity of the first emitted light. When the first output light travels in the +Z-axis direction, the output angle of the first output light is 0 degrees, and the first output light is directed in the normal direction of the first light output surface (in the example of FIG. 2, − If the output angle of the first output light when traveling in the Y-axis direction is 90 degrees, the intensity of the first output light when the output angle is 45 degrees is the same as the intensity of the first output light when the output angle is 90 degrees. greater than the strength of For example, the intensity ratio of the first output light when the output angle is 45 degrees to the intensity of the first output light when the output angle is 90 degrees is preferably within the range of 1.01 times to 10 times. More preferably, the range is from 1 to 5 times.

When considering the angular dependence of the intensity of the first emitted light, as a preferred configuration example of the diffuser 100, the size of the scattering structure (particle diameter in the case of particles) is in the range of 10 nm to 3000 nm. It may be within the range, more preferably from 50 nm to 2000 nm.

Further, the diffuser 100 may reproduce the color of a natural sky such as a blue sky (for example, transparent blue) by using Rayleigh scattering or similar scattering for incident light. good. Rayleigh scattering is a scattering phenomenon in which light with a short wavelength is preferentially scattered among light incident on a scattering particle. For example, when light in the visible wavelength band (approximately 350 nm to 850 nm) is incident, light in the blue wavelength band is preferentially scattered. Even in this case, when the light source 1 of the lighting device 200 emits visible light, the light L1 emitted from the diffuser 100 has a correlated color temperature higher than that of the light source 1. Here, Rayleigh scattering is a scattering phenomenon that occurs when the size of particles is smaller than the wavelength of light. In other words, when using light in the visible wavelength band as incident light to the diffuser 100, in order to obtain suitable scattered light that simulates a blue sky, the size of the scattering structure of the diffuser 100 (in the case of particles, particles The diameter) is preferably within the range of 10 nm to 800 nm.

Note that when the change in the viewing angle of the first light emitting surface by the observer is small, it is preferable that the in-plane brightness change of the first light emitting surface is small. In that case, the intensity of diffusion of the diffuser 100 is adjusted by the size, amount (concentration), etc. of the scattering structure, and the intensity of the first emitted light is set to be lower than the intensity of the second emitted light. You can. Further, as will be described later, by providing the diffuser 100 with two or more light entrance surfaces, it is possible to reduce the in-plane brightness change of the first emitted light with respect to the first light exit surface. With such a method, it is possible to reproduce a more natural sky while maintaining a thin structure.

For example, the thickness of the diffuser 100 can be 100 mm or less. Further, for example, the thickness of the diffuser 100 may be 20 mm or less, and may also be 10 mm or less. Furthermore, for example, the thickness of the diffuser 100 can be 5 mm or less. Furthermore, for example, if the size of the light source 1 (length in the Y-axis direction) is small, or if the light Li has a small irradiation range on the incident surface, such as light emitted from a laser light source or focused spot light, In some cases, the thickness of the diffuser 100 can be less than 1 mm.

Further, assuming that the diffuser 100 is a lighting panel that simulates the blue sky seen through a window on a clear day, the bright region 302 is the sunny region of the window sill on a clear day, and the dark region 301 is the shaded region of the window sill on a clear day. Preferably, the area can be simulated. In such a case, the bright region 302, that is, the pseudo-sunny region, is bright when the light is on, and the light L2 emitted from the bright region 302 is diffused, compared to the illumination function of the light L1 of the diffuser 100 when the light is on. It can be easily imagined that the color temperature is lower than that of the light L1 emitted from the first light emitting surface of the body 100. For example, the brightness of the blue sky during clear weather is about 5000 [cd/m2], and the brightness of the sunny area on a white diffuse reflection surface often used in window frame members is about 30000 [cd/m2]. . Additionally, the color temperature of the light when viewing the blue sky on a clear day is approximately 20,000 [K], and the color temperature of the light when viewing the sunny area on a white diffuse reflection surface is approximately 5,000 [K]. be. Therefore, it is desirable that the magnitude relationship between the brightness of the first light exit surface of the diffuser 100 and the bright area 302 and the color temperature of the light emitted from them be maintained as described above. However, the sky seen through the window is not limited to the blue sky on a clear day, but also includes rainy weather, cloudy weather, or both, and the brightness (or The ratio of the luminous flux emitted from them is more preferably within the range of 20:1 to 1:30.

Further, for example, the luminance of the first light exit surface of the diffuser 100 during lighting is 100 [cd/m2] to 6000 [cd/m2], more preferably 500 [cd/m2] to 3000 [cd/m2].
m2]. On the other hand, the brightness of the bright area 302 when lit may be 300 [cd/m2] to 30000 [cd/m2], more preferably 1000 [cd/m2] to 12000 [cd/m2]. . Further, the correlated color temperature of the light L1 emitted from the first light exit surface of the diffuser 100 may be 10,000 [K] to 100,000 [K], more preferably 20,000 [K] to 80,000 [K]. . On the other hand, the correlated color temperature of the light L2 emitted from the bright area 302 may be 2000 [K] to 7000 [K], more preferably 2500 [K] to 6500 [K].

Further, the difference in correlated color temperature between the light L1 emitted by the first light exit surface of the diffuser 100 and the light L2 emitted by the bright area 302 may be 20000K or more and 98000K or less. Further, the ratio of the brightness (or luminous flux) between the bright region 302 and the dark region 301 when the light is turned on is preferably within the range of 100:1 to 20:1, and more preferably about 10:1. However, this relationship is a condition that holds true when the sky is clear, and this does not apply under conditions such as cloudy weather or night.

<Sun formation part 3>
The sunlight forming part 3 is an optical member provided at at least one position around the diffuser 100 including the front side of the diffuser 100. Here, the periphery of the diffuser 100 is a concept that includes a space facing the side surface of the diffuser 100, a space facing the front surface, and a space facing the back surface of the diffuser 100. The sun forming part 3 is arranged so that, for example, the front surface, which is the side facing the space facing the first light exit surface, is visible to the viewer of the illumination device 200. Note that the space facing the first light emitting surface is a space from which the first emitted light is emitted, and may be hereinafter simply referred to as an irradiation space. The sunlight forming part 3 may be, for example, a frame-like member that imitates a surface facing the window (side wall) among the surfaces constituting the window frame.

The sunlight forming part 3 may be provided, for example, in a predetermined area in front of the diffuser 100 (see FIG. 1). Moreover, the sunlight forming part 3 may be provided, for example, in a predetermined area on the side of the diffuser 100 (see FIG. 7 described later).

The sun forming part 3 may be arranged so as to surround the irradiation space of the lighting device 200 (the space facing the light output surface 101b). For example, the sunlight forming part 3 may be arranged around the diffuser 100 so as to define the outer edge of the irradiation space. Here, the space around the diffuser 100 may be, for example, within 500 mm.

The sunlight forming part 3 may be arranged without any gap between the diffuser 100 and the front, rear, or side of the diffuser 100. At this time, the diffuser 100 and the sunlight forming part 3 may be connected, for example, with a cushioning material or the like interposed therebetween. By doing so, unnecessary light can be prevented from being emitted into the irradiation space of the lighting device 200.

The sun forming part 3 has at least a light-transmitting member. The sunlight forming part 3 directs second emitted light (light L2) emitted from a second light emitting surface (light emitting surface 101c) of the diffuser 100 and deflected by a folding part 2, which will be described later, into an irradiation space. The light is emitted toward (the space facing the light emitting surface 101b). Note that the example shown in FIG. 1 is an example in which the sun forming part 3 is formed of a light-transparent member. Moreover, the sun forming part 3 may further include a light transmitting and diffusing member. In that case, the sunlight forming part 3 emits second emitted light (light L2) that is emitted from the second light emitting surface (light emitting surface 101c) of the diffuser 100 and is deflected by the folding part 2, which will be described later. The light is emitted toward the irradiation space through diffuse transmission or diffuse reflection. The light transmitting and diffusing member is made of, for example, a sheet material such as a transmitting and scattering sheet or a film material, and is arranged on the surface of the sunlight forming part 3 on the space side. Moreover, the sunlight forming part 3 may contain scattering particles therein as a light transmitting and diffusing member. In order to improve light utilization efficiency, it is desirable that the transmittance of the sunlight forming part 3 is high.

<Folded part 2>
The folding section 2 is a light guide that deflects the second emitted light (light L2) emitted from the second light emitting surface (light emitting surface 101c) of the diffuser 100 into light directed toward the sunlight forming section 3. It is a member. The folded portion 2 has at least one reflective surface. The folded portion 2 may be, for example, an optical member having a reflective film or a reflective structure on its surface. For example, the folded portion 2 may be made of a material with high reflectance such as aluminum, or may be made of a refractive material that performs internal reflection as shown in FIG. 6, which will be described later.

FIG. 3 is an explanatory diagram showing the optical path of the second emitted light to the sunlight forming part 3. In the example shown in FIG. 3, the lighting device 200 includes two folded parts 2. In this way, the second emitted light (light L2) is guided toward the sunlight forming part 3 by at least one folding part 2.

Note that, in addition to the second emitted light, the folding section 2 also absorbs light emitted from a surface other than the second light exit surface of the diffuser 100 and light emitted from the light source 1 without going through the diffuser 100. The light that has reached the end side of the diffuser 100 to be formed may be guided toward the sunlight forming part 3. For example, in the case of a configuration in which there is a gap between the back surface of the diffuser 100 and a back plate 4 (or the holding part 6 in the case where the back plate 4 is not provided), which will be described later, light from the light source 1 passes through the gap. Li may reach the opposite end of the light incident surface 101a of the diffuser 100, which is the end where the folded portion 2 is formed. In such a case, the folding section 2 directs the light Li that has passed through the gap and reached the end side where the folding section 2 is formed from the light source 1, in addition to the second emitted light. The light may be guided towards 3.

<Light source 1>
The light source 1 is provided opposite to an end surface constituting an end of the surface 101b on which the main light emitting surface of the diffuser 100 is formed. For example, the light source 1 includes a light emitting surface that emits light Li that becomes incident light to the diffuser 100, and is arranged such that the light emitting surface faces the end surface of the diffuser 100. Note that it is also possible to provide a plurality of light sources 1 for one diffuser 100. In this embodiment, a group (including one light source) or light emitting element that emits incident light Li to one diffuser 100 is collectively referred to as a light source 1.

The light source 1 emits light Li that is incident light to the diffuser 100. The light source 1 emits, for example, white light as light Li. Further, the light source 1 may emit light having a predetermined correlated color temperature Tci as the light Li, for example.

The correlated color temperature Tci is, for example, 6500K. Further, the correlated color temperature Tci is, for example, 5000K. The correlated color temperature of the light emitted by each light source may be the same or may be different.

The color of the light Li emitted from the light source 1 may be other than white. For example, the light source 1 can include a white light source and a green light source. Further, the light source 1 can include a white light source, a green light source, and an orange light source. Furthermore, the light source 1 can include white light sources with different color temperatures. For example, the light source 1 can include a high color temperature white light source and a low color temperature white light source.

Here, the difference in color temperature between white with a high color temperature and white with a low color temperature is, for example, 8800K. The correlated color temperature of white with a high color temperature is, for example, 14400K. The correlated color temperature of white with a high color temperature is, for example, 11,500K or higher. Further, the correlated color temperature of white having a high color temperature is, for example, 19000K or less. The correlated color temperature of white with a low color temperature is, for example, 5600K. The correlated color temperature of white with a low color temperature is, for example, 5500K or higher. Further, the correlated color temperature of white with a low color temperature is, for example, 6050K or less.

Note that the configuration example of the light source 1 and the example of the color temperature of the light Li emitted from the light source 1 described above are just examples, and the diffuser 100 is It is adjusted as appropriate in conjunction with the configuration of .

Note that the light source 1 may be disposed facing one end surface of the diffuser 100, or may be disposed facing two or more end surfaces of the diffuser 100 (see FIG. 8 described later). . Note that from the viewpoint of uniform irradiation of the first emitted light from the first light emitting surface, when the main surface shape of the diffuser 100 is rectangular, the light source 1 is connected to the longitudinal side of the main surface of the diffuser 100. It is preferable that it be provided opposite to the end surface connected to. In this case, the light incident surface 101a is formed on the end surface connected to the longitudinal side of the main surface of the diffuser 100.

Further, as shown in FIG. 8, when the light source 1 is arranged to face two or more end faces of the diffuser 100, the end faces may not face each other.

As the light source 1 included in the lighting device 200, for example, a tube light source such as an incandescent lamp, a halogen lamp, or a fluorescent lamp may be used. Further, as the light source 1, for example, a semiconductor light source such as a light emitting diode (LED) or a laser diode (LD) may be used. That is, the structure, principle, etc. of the light source 1 are not particularly limited, and any light source may be used. However, from the viewpoint of reducing the burden on the environment by suppressing carbon dioxide (CO2) emissions and fuel consumption, a semiconductor light source is preferable as the light source 1. Semiconductor light sources are desirable because they have higher luminous efficiency than conventional lamp light sources typified by halogen bulbs, and are easy to reduce in size and weight. Semiconductor light sources have higher directivity than conventional lamp light sources, allowing optical systems to be made smaller and lighter.

Furthermore, for example, in consideration of ZEB (Zero Energy Building), it is also possible to replace the light Li with light obtained by guiding external light (such as sunlight). For guiding external light, a lighting member or a light guiding body that takes in external light and emits it in a predetermined direction can be used. In that case, the light source 1 may be such a lighting member or a light exit surface of a light guide.

<Back plate 4>
As already explained, the lighting device 200 may include the back plate 4. The back plate 4 is provided on the back side of the diffuser 100 (in the -y axis direction in this example). The back plate 4 may be provided facing the back surface (surface 101d) of the diffuser 100. Note that it is preferable that the distance between the back plate 4 and the diffuser 100 be short. Note that the back plate 4 is an example of a light reflecting member or a light absorbing member provided on the back side of the diffuser 100.

The back plate 4 has a reflective function or is opaque, and has a transmittance of preferably 50% or less, more preferably 10% or less.

The back plate 4 is preferably a diffuse reflector, more preferably a white diffuse reflector. The back plate 4 may be a light absorber. The back plate 4 may be made of a highly reflective metal member such as aluminum. Note that the back plate 4 is not limited to a flat plate shape. The back plate 4 may be curved or inclined, for example, or may be a combination of such a flat surface, a curved surface, or an inclined surface. Further, the back plate 4 may be made of a sheet material such as a reflective sheet or a film material, for example. Alternatively, at this time, the back plate 4 may have a specular reflection effect or a diffuse reflection effect (for example, a reflection effect such as Lambertian reflection or Gaussian reflection).

In addition, the opening and closing states of the back plate 4 may be changeable. Since the back plate 4 is provided so that it can be opened and closed, when the user wants to view the back side space or take in outside light, the back plate 4 is opened and the back side space is viewed through the diffuser 100. In addition, the lighting device 200 can also be used as a window. The opening and closing state of the back plate 4 may be changed, for example, like a blind or a shutter, by folding the back plate 4 or storing it in a door pocket.

The shielding state of the back plate 4 may be changeable by applying a voltage to the back plate 4, for example, like a liquid crystal shutter. The shielding state of the back plate 4 may be changeable by applying a voltage to the back plate 4, for example, like a liquid crystal panel.

Further, the back plate 4 may be supported integrally with the diffuser 100 within the holding portion 6. In that case, the back plate 4 may be integrally supported with the diffuser 100 so as to be openable and closable.

The back plate 4 reflects, for example, out of the light incident on the diffuser 100, the light exiting from the surface 101d (back surface) toward the −Y-axis direction by transmission, light guiding, or scattering. The light reflected by the back plate 4 can be converted into light L1 and light L2 by the transmission, light guide, or scattering effect of the diffuser 100, so that the light utilization efficiency of the entire lighting device can be improved.
Further, when the lighting device 200 is also used as a window, the light emitted to the back side may cause light pollution to people who are outdoors or on the back side. In such a case, the back plate 4 can reduce light leakage to the back side.

<Light shielding part 5>
As already explained, the lighting device 200 may include the light shielding part 5. The light shielding part 5 is made of a reflective material or a light absorbing material. The light shielding part 5 is provided in order to suppress the first emitted light (light L1) from entering the sunlight forming part 3 via the irradiation space. Moreover, the light shielding part 5 suppresses the second emitted light (light L2) from entering the diffuser 100 via the space facing the sunlight forming part 3 (this is a concept that includes the irradiation space). established for the purpose of

The light shielding part 5 is provided, for example, at least at one position between the diffuser 100 (particularly the first light exit surface) and the sun forming part 3. The light shielding section 5 is configured such that when the first output light is emitted to the entire possible output range of the first output light (light L1) without providing the light shielding section 5, the first output light is emitted from the sunlight forming section. It is preferable that the light beam be provided at at least one position on the optical path where the optical path is reached so as to block the optical path. Further, the light shielding section 5 is configured such that when the second outgoing light is emitted to the entire range where the second outgoing light (light L2) can be emitted without providing the light blocking section 5, the second outgoing light is transmitted to the diffuser 100. It is preferable that the light be provided at at least one position on the optical path that reaches the first light exit surface of the optical path so as to block the optical path. Note that FIG. 1 shows an example in which the light shielding part 5 is provided on the main surface of the diffuser 100.

By providing such a light shielding part 5, the illumination function of the first light emitted from the first light emitting surface and the illumination function of the second light emitted from the sun forming part 3 are achieved. By separating them, it is possible to suppress unnecessary light from being reflected on the diffuser 100 and the sunlight forming section 3.

<Modified example>
FIG. 4 is a configuration diagram showing another example of the lighting device 200 according to the first embodiment. As shown in FIG. 4, the lighting device 200 may further include a color conversion member 7. The color conversion member 7 converts the second emitted light (light L2) emitted from the diffuser 100 in order to emit light with a good color temperature from the sunlight forming part 3. Specifically, the second emitted light emitted from the diffuser 100 is converted into light having a correlated color temperature lower than that of the second emitted light. Hereinafter, the unconverted second emitted light of the color conversion member 7 may be referred to as light L21, and the unconverted second emitted light of the color conversion member 7 may be referred to as light L22. Here, the color temperature of the light L22 is lower than the color temperature of the light L21. The color conversion member 7 is, for example, a color filter or a transparent resin or sheet in which a phosphor element is encapsulated. It is desirable that the color conversion member 7 has high transmittance in order to improve light utilization efficiency.

The color conversion member 7 is provided, for example, on the optical path of the second emitted light from the second light emitting surface (light emitting surface 101c) of the diffuser 100 to the sunlight forming part 3. Note that FIG. 4 shows an example in which the color conversion member 7 is arranged in contact with the back surface of the sunlight forming part 3. Note that the arrangement of the color conversion member 7 is not limited to this. For example, the color conversion member 7 may be placed in contact with the second light exit surface, and in that case, it may be formed integrally with the diffuser 100.

Further, FIGS. 5 and 6 are configuration diagrams showing other examples of the folding section 2. As shown in FIG. In the above-described example, the reflective surface of the folded portion 2 is a flat surface, but the shape of the reflective surface of the folded portion 2 is not limited to a flat shape, and may be, for example, a curved shape. Further, the folded portion 2 may be a light guiding member made of a refractive material, as shown in FIG. 6 . In that case, the second emitted light is guided inside the light guide member and guided to the sun forming part 3 using internal reflection of the light guide member. The light guide member may be, for example, a polyhedron. The light guide member may be made of, for example, a transparent resin with high transmittance.

Further, FIG. 7 is a configuration diagram showing another example of the sun forming section 3. As shown in FIG. In the example described above, the sun forming part 3 was arranged perpendicularly (90 degrees) to the first light emitting surface (light emitting surface 101b) of the diffuser 100, but the sun forming part 3 , may be arranged so as to be inclined with respect to the first light exit surface. At this time, the inclination angle θ of the sun forming part 3 is desirably 90 degrees to 150 degrees based on the angle of the first light exit surface on the YZ plane. Here, θ may be an angle of the front surface (surface on the irradiation space side) of the sun forming part 3 with respect to the first light exit surface.

This is because when the lighting device 200 is attached to a ceiling or a wall surface, the second emitted light emitted from the sunlight forming part 3 is used as illumination light. Furthermore, by simulating the state in which the sunlight forming part 3 is illuminated by sunlight coming in through the window, a more natural landscape can be reproduced.

Further, FIG. 8 is a front view showing an example of the lighting device 200 according to the first embodiment, and FIG. 9 is a perspective view of the lighting device 200 shown in FIG. 8. As shown in FIG. 8, for example, the lighting device 200 can include one or more light sources for a plurality of sides of the main light emitting surface of the diffuser 100. FIG. 8 shows an example in which light sources are arranged on two sides (sides a and b) that are not facing each other among the four sides (sides a to d) of the main light emitting surface of the diffuser 100. has been done. Note that the sun forming portions 3 are provided around the ends corresponding to each of the four sides. In FIG. 8, the light source 1 provided on the side a side is shown as a light source 1a, and the light source 1 provided on the side b side is shown as a light source 1a. In addition, in FIG. 8, the sun forming part 3 provided around the end of side a side is a sun forming part 3a, and the sun forming part 3 provided around the end part of side b side is a sun forming part 3a. Forming part 3b, the sun forming part 3 provided around the edge on the side c side is referred to as a sun forming part 3c, and the sun forming part 3 provided around the end on the side d side is referred to as a sun forming part 3d. Here, sides a and c are opposite to each other, and sides b and d are opposite to each other.

In this example, the light emitted from the light source 1a enters from the light entrance surface provided at the end of the side a of the diffuser 100. Then, a part of the light that has entered the diffuser 100 is emitted as second emitted light (light L2) from the second light emitting surface provided at the end on the opposing side c side, and passes through the folded part 2. The light passes through and is emitted from the sunlight forming part 3c. Further, the light emitted from the light source 1b enters from the light entrance surface provided at the end of the side b side of the diffuser 100. Then, a part of the light that has entered the diffuser 100 is emitted as second emitted light from the second light emitting surface provided at the end of the opposing side d, passes through the folded part 2, and is exposed to sunlight. The light is emitted from the formed portion 3d. That is, among the sun forming parts 3a, 3b, 3c, and 3d, the second emitted light is emitted from the sun forming part 3c and the sun forming part 3d, so that the sun forming part 3c and The sunlight forming portion 3d emits light. Thereby, the sun-forming part 3c and the sun-forming part 3d can simulate being illuminated by sunlight.

At this time, the second outgoing light is emitted from the sun forming part 3c in the -Z direction, and the second outgoing light is emitted from the sun forming part 3d in the +X axis direction. In the case of this example, the illumination device 200 can simulate sunlight Cr as shown by the angle in the figure. The simulated sunlight Cr in the figure appears to be shining in the −X-axis direction, −Y-axis direction, and +Z-axis direction.

Note that the second emitted light emitted from the sun forming part 3c in the −Z direction is configured to faintly illuminate the surface of the sun forming part 3a provided on the opposing side a. You can. Similarly, the second emitted light emitted from the sun forming part 3d in the X direction faintly illuminates the surface of the sun forming part 3b provided on the opposing side b side. You can. The phenomenon in which the opposite surface is illuminated by the reflection of the light shining on the window frame is a phenomenon that can actually be seen during the day when the sun is strong. With this configuration, a more natural landscape can be reproduced.

In this example, the first emitted light (light L1) is isotropically emitted from the first light emitting surface toward the −Y-axis direction.

Moreover, FIG. 10 is a sectional view showing another example of the lighting device 200 according to the first embodiment. FIG. 11 is a cross-sectional view of the lighting device 200 shown in FIG. 10, viewed from the +Z-axis direction. Note that FIG. 11(A) is a cross-sectional view showing an example of the physical configuration of the lighting device 200 shown in FIG. 10, and FIG. FIG. Moreover, FIG. 12 is a perspective view showing the example of the illumination device 200 shown in FIG. 10 as seen from an observer.

As shown in FIGS. 10 and 11(A), the lighting device 200 can further include a light amount adjustment section 8. Further, in this example, the sunlight forming section 3 includes a dark region 301 and a bright region 302. Here, the dark area 301 is an area that simulates a sunshade formed on the sunlight forming part 3 by the light inserted from the sun. The bright area 302 is an area that simulates the sunlight formed by the inserted light on the sunlight forming part 3.

The light amount adjustment unit 8 adjusts the intensity of the light that is incident on the sunlight forming unit 3 from the dark area 301 toward the irradiation space of the illumination device 200 (the space facing the light output surface 101b). It may also be a light limiting member that weakens the intensity of light directed from the irradiation space toward the irradiation space. The light limiting member is also called a mask. The light amount adjustment unit 8 is configured such that the light incident on the sunlight forming unit 3 is incident on the front surface (the surface on the irradiation space side) of the sunlight forming unit 3 or the back surface thereof, so that the light entering the sunlight forming unit 3 is adjusted. The light is disposed at least in a region corresponding to the dark region 301 on the optical path from the front surface to the light emitted toward the irradiation space. Here, the above-mentioned optical path includes not only the optical path from the diffuser 100 to the sunlight forming section 3 but also the second optical path facing from the first sunlight forming section 3 with the irradiation space in between. The optical path up to the sun forming part 3, the optical path inside the sun forming part 3, and the surface of the sun forming part 3 are included.

In addition, the area corresponding to the dark area 301 on the optical path means that when light traveling along the optical path passes through that area at an arbitrary position on the optical path (position in the light traveling direction), the area corresponds to the dark area 301. This refers to an area where light travels from the dark area 301 on the machete forming part 3 toward the irradiation space. Similarly, the area corresponding to the bright region 302 on such an optical path is the area where light traveling along the optical path passes through that area at any position on the optical path (position in the light traveling direction). , refers to an area where light travels from the bright area 302 on the sunlight forming part 3 toward the irradiation space.
.

The light amount adjustment section 8 has, for example, a light shielding function that prevents a part of the second emitted light (light L2) from reaching the sunlight forming section 3. The light amount adjustment section 8 may be an optical member that absorbs or reflects at least a portion of the incident light. In order to improve the light utilization efficiency, it is preferable that the light amount adjustment section 8 is made of a member with high reflectance.

By providing such a light amount adjusting section 8, the dark region 301 formed in at least one sun forming section 3 can be changed to the dark region 301 formed in the sun forming section 3 or another sun forming section 3. The viewer visually recognizes the area as a darker area than the bright area 302.

In addition, in the example shown in FIG. 10 and FIG. 11(A), the light amount adjustment part 8 is arrange|positioned in contact with the back surface of the sunlight forming part 3. In the case of this example, the dark area 301 formed on the sunlight forming part 3 has the same shape as the light amount adjusting part 8 (see FIG. 11(B)).

Further, FIG. 12 is a perspective view showing an example of the illumination device 200 as seen from the observer when light sources are provided on two adjacent sides (sides a and c) of the diffuser 100, similar to the example shown in FIG. It is. In this example, the light emitting state is divided into a dark region 301 and a bright region 302 in the sunlight forming portion 3c and the sunlight forming portion 3d, respectively. That is, in the sunlight forming section 3c, the light emitting state is divided into a dark region 301c and a bright region 302c, and in the sunlight forming section 3d, the light emitting state is divided into a dark region 301d and a bright region 302d. . Note that the shapes of the dark area 301c, bright area 302c, dark area 301d, and bright area 302d simulate the state of the window frame when simulated sunlight Cr is blocked by the light shielding part 5 and the holding part 6. (See also FIG. 10).

By providing such a light amount adjustment section 8, it is possible to integrate the sky simulating function by the diffuser, and it is possible to reproduce a more natural skylight or wall window.

As described above, according to the above embodiment and its variations, the light source for simulating the sky seen through the window and the light source for simulating the incoming light that illuminates the window frame are shared, and the size is further reduced. In addition to simplifying the structure, natural landscapes can be reproduced without any restrictions on the location or number of locations.

200 Illumination device 100 Diffuser 101a Light entrance surface 101b Light exit surface (first light exit surface)
101c Light exit surface (second light exit surface)
101d Back surface 110 Base material 111 Particles 1, 1a, 1b Light source 2 Folded portion 3, 3a, 3b, 3c, 3d Sunlight forming portion 301 Dark region 302 Bright region 4 Back plate 5 Light shielding portion 6 Holding portion 7 Color conversion member 8 Light amount adjustment section

Claims (13)

a light source and
a first light exit surface that has a scattering structure that scatters the incident light, and that emits at least one light entrance surface and a first exit light that includes the scattered light generated by the scattering structure; a second light emitting surface that emits a second emitted light different from the emitted light, and receives light from the light source to generate the first emitted light and the second emitted light; body and
a sunshade forming part that is provided at at least one position around the diffuser, has a light-transmissive member, and forms a sunshade using the second emitted light ;
a folding section that guides the second emitted light toward the sunlight forming section;
a light shielding part provided at at least one position between the first light emitting surface and the sun forming part and blocking the first emitted light from entering the sun forming part; A lighting device comprising: The first emitted light is emitted from the first light emitting surface into a space facing the first light emitting surface,
The lighting device according to claim 1, wherein at least a portion of the second emitted light is deflected by the folding portion and emitted from the sunlight forming portion toward the space. The second emitted light includes light that was not scattered by the scattering structure among the light that entered the diffuser,
The illumination device according to claim 1 or 2, wherein a correlated color temperature of the first emitted light is higher than a correlated color temperature of the second emitted light. The lighting device according to any one of claims 1 to 3, wherein the intensity of the first emitted light is lower than the intensity of the second emitted light. The light entrance surface is located at a first end of the first light exit surface,
The second light exit surface is located at a second end opposite to the first end of the first light exit surface. lighting equipment. The lighting device according to any one of claims 1 to 5, wherein the first light exit surface is rectangular or square. The lighting device according to any one of claims 1 to 6, wherein the light source and the sunlight forming section are arranged at positions facing each other with the diffuser interposed therebetween. The illumination device according to any one of claims 1 to 7 , further comprising a color conversion member on the optical path of the second emitted light from the second light output surface to the sunlight forming part. . The sunlight forming part includes a dark area and a bright area,
A light amount adjustment unit is provided that weakens the intensity of light traveling from the dark region toward the irradiation space of the illumination device among the light incident on the sunlight forming section than the intensity of the light traveling from the bright region toward the irradiation space. The lighting device according to any one of claims 1 to 8 . The illumination device according to any one of claims 1 to 9 , wherein the size of the scattering structure is within the range of 10 nm to 3000 nm. The illumination device according to any one of claims 1 to 10 , wherein the angle of the front surface of the sunlight forming part with respect to the first light exit surface is within a range of 90 degrees to 150 degrees. The first light emitting surface simulates the sky seen through the window by the first emitted light emitted from the first light emitting surface,
The sunlight forming section simulates the incoming light that illuminates the window frame by the second emitted light emitted from the sunlight forming section. lighting equipment. The diffuser has two or more light incident surfaces,
A plurality of the first light emitting surfaces, the second light emitting surfaces, the folding portions, and the sun forming portions are provided corresponding to each of the two or more light incident surfaces. 12. The lighting device according to any one of 12 .

Images